I have a Canon 40D and a Canon 17-55 f2,8. I am not pleased with the sharpness of my pictures. I would like to buy a Nikon D300S, but my problem is which lens. Should I go for the 16-85 or the 18-200. I want a lens that is really sharp.

I know the D300S just have got 12,3 MP and the new Canon EOS 7 D has got 18 MP, but I am just thinking that because I am not pleased with the Canon equipment, I should change to Nikon.

As pleased as I am by my 16-85, it's no sharper, and doesn't have the wider aperture.

I know this is a Nikon thread, but if you want greater sharpness, you might really be worth testing the same lens with the Canon 7D, though ultimately FX would be the way to go if critical sharpness or big enlargements are your goals.

Otherwise, I believe that the 40D has slightly soft JPEGs, and raw performance may be better. A lot of this sort of thing has to do with the JPEG program the particular manufacturer uses, and some may even be down to the anti-aliasing filter (which is usually stronger on Nikons than Canons, I think).

There may be other reasons you wish to switch to Nikon, in which case you can disregard my comments.

If you're looking for razor sharp images with that lens, you have to shoot at F4. F2.8 will always be softer on an APS-C camera. I dont shoot F2.8 too much other than outdoor portrait or lowlight. I prefer F4 since it is about the sharpest that lens can get.

Most of my shots are handheld. The ISO is normally 100-200. AF is always on. I try to shoot at f8. IS is on.

I have tried to put my camera on a tripod using the self-timer, but the result are the same (not very sharp). The camera and the lens has been checked by a Canon repairshop and they were found to be "spot on".

I shoot JPEG and I do some sharpening (unsharp mask) in Photoshop Elements 7.0 I also enhanche the pictures by gently changing the saturation, exposere, contrast etc.

The Canon lens is not a L-lens.

In the past, when I was shooting on film, I always used Nikon, but I bought the Canon when I got into "the Digital World".

I suggest a test where you afix the camera to a tripod and turn off image stabilization and use live view to manually focus exactly aligning the object to center AF point on something which has a strong profile, such as a frayed piece of fabric or a leaf. Use self timer to take the shot.

Then repeat the test with AF on. Using Mirror lock up and self timer still on the tripod and keep image stabilization turned off .

Compare both shots.

If the AF on shot is blurry, then perhaps your AF focus needs a micro tune adjustment for the particular lens.

It sounds like Erik has taken the basic troubleshooting steps to confirm that it's not his technique that is the problem.

I assume that you've seen some samples and reviews of the 17-55 online. How far off is what you are getting from what you see online? The 17-55 isn't the sharpest lens around but it's not slouch either.

Hello Erik, and welcome to the friendly Camera Labs forum!
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The Canon lens should give you very decent sharpness if everything is a-ok. capital has already given you some good advice as how to test what may result in soft images. Dirty front-/back-lenses or smear on the sensor also belong in this category. Look carefully.
The next best thing would be to post some of the images (100% crops) that you are dissatisfied with. That would give our evaluation some real good fodder.